N-(Azido-PEG2)-N-bis(PEG4-Boc) | CAS 2112731-81-2

N-(Azido-PEG2)-N-bis(PEG4-Boc) is a PEG-based azide-functional click chemistry reagent designed for strain-promoted or copper-catalyzed azide–alkyne cycloaddition workflows. The molecule combines a short PEG2 azide handle with two longer PEG4 Boc-protected substituents, providing a compact, water-compatible scaffold that can be carried through labeling, surface modification, and biomaterials functionalization steps. Its protected groups and flexible PEG architecture make it a practical intermediate for building azide-bearing conjugates and for tuning solubility and reactive density in downstream research and materials applications.

1. Biomolecule PEGylation Handles

N-(Azido-PEG2)-N-bis(PEG4-Boc) is commonly used as an azide-bearing PEG linker for preparing PEGylated biomolecule conjugates where a defined click handle is required for subsequent attachment to alkyne-functional partners. Researchers often incorporate this reagent into labeling strategies for proteins, peptides, and nucleic-acid-associated constructs to improve aqueous handling and to modulate conjugate spacing. The PEG-rich design supports reduced nonspecific interactions in many assay and imaging workflows, while the azide functionality enables modular coupling to fluorescent tags, affinity reagents, or other probe scaffolds that are introduced later through click chemistry.

2. Surface And Material Functionalization

N-(Azido-PEG2)-N-bis(PEG4-Boc) is well suited for functionalizing polymeric and biomaterial surfaces that need an azide presentation for orthogonal coupling to alkyne-bearing coatings, linkers, or nanoparticles. In materials science and chemical biology, the reagent is used to introduce PEG-mediated spacing between a surface and the eventual ligands, which can be important for controlling accessibility and reducing steric hindrance. The Boc-protected components also support stepwise build strategies in which the material is first prepared with a stable PEG/azide intermediate and then advanced to a final functional state using subsequent deprotection and click-based assembly.

3. Fluorophore And Probe Conjugation

N-(Azido-PEG2)-N-bis(PEG4-Boc) supports the construction of azide-functional imaging and detection probes by providing a flexible PEG spacer that can improve solubility and help maintain probe performance in complex labeling buffers. Probe developers frequently use this reagent to generate click-ready conjugation intermediates that are later coupled to alkyne-functional dyes, quencher units, or affinity tags in a modular fashion. The PEG architecture helps tune the effective hydrodynamic environment around the probe, which is often relevant for multicomponent labeling schemes and for minimizing aggregation during probe preparation and storage.

4. Diagnostic Reagent Building Blocks

N-(Azido-PEG2)-N-bis(PEG4-Boc) is used in the development of diagnostic and assay reagents where azide–alkyne click chemistry provides a robust route to assemble multivalent reagent formats. Assay developers employ azide-functional PEG linkers to control conjugate architecture, spacing, and reagent solubility when attaching detection moieties to capture surfaces or to soluble assay components. The reagent’s modular nature aligns with common downstream workflows that require pre-assembled intermediates, enabling consistent coupling to standardized alkyne-bearing components used across reagent platforms.